Call of Duty: World at War features a more mature theme than previous installments in the series. The game is also open-ended, as there are multiple ways to complete objectives. The gameplay of World at War shares features with previous iterations of the franchise. Players fight alongside AI-controlled teammates, who help during the game's missions by providing cover fire, shooting enemies, and clearing rooms for entry.

Gameplay on the Wii version of the game can be controlled with a gun-like expansion controller known as the Wii Zapper. The Zapper, or Wii Remote and Nunchuk, can be used to aim at targets to simulate marksmanship.